Gliederung

Objective: There is controversy among cerebrovascular scientists on the time span over which cerebral aneurysms develop. Whether ruptured aneurysms are present for a short time before rupture and therefore contain new or young collagen, while unruptured aneurysms might consist of more mature collagen types remains unknown. In this respect, the rapid increase of atmospheric 14C as a consequence of atmospheric nuclear testing from 1955–1963, might facilitate the determination of the age of ruptured and unruptured aneurysms by using 14C-birth dating.

Methods: Aneurysmal domes from patients undergoing surgical treatment for a ruptured or unruptured aneurysm were excised. Aneurysmal collagen was isolated and purified using a pepsin digestion assay. Samples from dura and extracranial blood vessels served as controls. Lyophillized collagen samples were then analyzed for 14C-levels using accelerator mass spectrometry (AMS; Livermore, CA, USA).

Results: A total of 48 aneurysmal domes (27 ruptured, 21 unruptured aneurysms) were retrieved after surgical clipping. To date, 19 samples were analyzed using AMS to determine 14C-levels. The average yield of carbon was 0.30 Â± 0.28 mg. The average age of the collagen from these aneurysms was less than 10 years, regardless of the age of the patient (mean 57.41 Â± 12.76). Lastly, there was no correlation between age of collagen and aneurysm rupture status with samples analyzed.

Conclusions: Our preliminary data suggests that collagen extracted from ruptured or unruptured intracranial aneurysms is distinctively younger than the individual patient harbouring the aneurysm. This might challenge assumptions on differences in collagen turnover and, consecutively, progression intervals between ruptured and unruptured intracranial aneurysms. These findings are preliminary but may eventually have implications for radiological screening of the general population for aneurysms.